Rite Aid has expanded an online doctor service for its drugstore customers that is limited to virtual visits but cheaper than a traditional primary care appointment.

The company, the nation’s third-largest drugstore operator with 4,600 U.S. stores, said Friday that its NowClinic Online Care program is available at 58 locations in four cities: Baltimore, Boston, Philadelphia and Pittsburgh. Its rivals, Walgreen and CVS, also run in-store clinic programs. Walgreen operates more than 370 Take Care clinics, while CVS runs more than 600 MinuteClinics.

Rite Aid’s service connects drugstore customers with doctors for a video or phone consultation about a range of ailments like allergies, bronchitis, rashes, the flu or sinus infections. Rite Aid officials say the concept aims to improve access to health care. The drugstore’s effort comes less than a year before a wave of new patients is expected to hit the health care system when the federal health care overhaul expands insurance coverage to millions. Some are worried about primary care doctors’ ability to keep up with the expected influx of patients.

“It’s just one more avenue for someone who needs some form of acute care medical attention to get it,” said Robert Thompson, Rite Aid’s executive vice president of pharmacy. “It’s certainly easier than going to the emergency room.”

Insurers don’t cover Rite Aid’s online care service, but it is less expensive than other types of care.

The 10-minute doctor consultations cost $45, while a doctor’s office visit could cost someone without insurance more than $100 and an emergency room bill might run several hundred dollars.

Doctors can write prescriptions after consulting with patients, or they can refer them elsewhere for more extensive care. Customers also can have video or phone chats for free with a nurse, who can give them information on common conditions or help them figure out the right health care provider.

Thompson said the service uses a secure technology platform built for doctor-patient interaction, so privacy is preserved.

“You’re not Skyping with a doctor,” he said.

Rite Aid operates the service in drugstore consultation rooms used by pharmacists for immunizations or to talk to patients. Patients can take their temperature and measure their weight and blood pressure to help with the consultation. People also can access Rite Aid’s doctor service from desktop or laptop computers from outside the drugstore.

The drugstore chain started this concept in 2011 and has been testing it at pharmacies in Detroit, Pittsburgh and Harrisburg, Pa., near Rite Aid Corp.’s Camp Hill headquarters. Rite Aid also run about 16 in-store clinics at stores around the country, through partnerships with regional health care systems.

The virtual clinics are part of a push by Rite Aid to make its stores more productive, said Mary Gilbert, an analyst who covers the company for the investment bank Imperial Capital. She said CVS Caremark and Walgreen locations typically fill between 1,600 and 1,900 prescriptions every week, while Rite Aid stores fill about 1,150.

Neither of those chains offers virtual consultations, but they staff their clinics with nurse practitioners or physician assistants. Rite Aid does not, although it says pharmacists are available at the store locations to help customers.

The analyst said the concept won’t have a material impact on Rite Aid’s business, but that could change over time. She thinks there’s a market for the service.

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